Too Close to the Moon
by LadyMoriel
Summary: Crossover with Harry Potter. Ten, Rose, Remus, and Tonks save the world from our friend the alien werewolf, last seen in Tooth & Claw. RT, hints of Ten/Rose.


**Title:** Too Close to the Moon  
**Author:** LadyMoriel  
**Fandoms:** Doctor Who, Harry Potter  
**Rating:** PG  
**Characters:** Ten, Rose, Remus Lupin, Nymphadora Tonks  
**Pairings:** Remus/Tonks, a tiny bit of implied Doctor/Rose  
**Prompt:** "Remus Lupin, Ten, werewolves"  
**Warnings:** A very little bit of violence, and some Dark Arts nonsense with blood and such. I did have a bit of trouble writing this story, mostly because I'd never written a crossover before (you might notice I had some trouble making two semi-incompatible fandoms collide with the result of the characters involved all cooperating with each other, at least without lots of talking), partly because I haven't written something with a plot in, seriously, _forever_, and partly because, um, I started late as usual and then wrote the whole thing in like a week and a half. Staying up late several nights and writing in class to do so, I might add. The end result is a ridiculously long story that consists largely of Ten getting to be Exposition Boy and me Making Crap Up. (For what it's worth, I'm aware of the use of _Impervius_ in the books, but I needed something for this function, and fernwithy used it just like this in _Shades_. Might as well copy from a good fanwriter if you're going to use semi-dubious fanon, right? And I also decided to ignore the sticky problem posed by the Harry Potter references in "The Shakespeare Code." Because…it was long enough and there was already too much expository dialogue.) Any mistakes in Britspeak (and I'm sure there are some) are…pretty much all my fault, but you can also blame Google for not leading me to the right sites.  
**Author's notes:** Takes place in early OotP and some time in DW season 2 after "The Idiot's Lantern" (because of a minor reference, but the only important thing is that you've seen "Tooth and Claw"). Written for a Doctor Who crossover fic exchange. This was going to be the first of a two-parter, the second part of which I hope to write eventually, because one of my other two prompts was for a DW/HP/Supernatural crossover: "Sam Winchester / Remus Lupin / Ten". And of course my idea for that developed before my idea for this story, and I liked it better, but it was after this one chronologically, so I decided I'd better write this one first. And then I ran out of time. So…anyone who cares can look forward to that, or not, and in the meantime you can assume that anything in this fic that seems to foreshadow something that never happens is a reference to that second part.

* * *

"Werewolves," Rose said. "Again?" 

The Doctor fiddled with a knob on the console. "Looks like we were right about old Vicky back there—she got the whole werewolf unpleasantness, passed it along to her kids, the alien cell kept growing, and a few hundred years down the line—"

"Let me guess, an alien werewolf wants to take over the world?"

"Always up to something, isn't he?" he agreed. "I'm guessing—and chances are I'm right—the kids weren't so careful and ended up spreading it to a few others, so we've got a line of werewolves and a whole load of nasty business when the alien part finally takes over. More than one of them, probably, whether or not they're actually alien."

"More than one werewolf," Rose repeated. "Yeah, so what's the bad news?"

"No idea what to do about them. Should be interesting—" The TARDIS jolted suddenly, and the Doctor dove for a row of switches. "Oops, hang on—"

Rose gripped the console. The TARDIS bucked and shimmied around her for several seconds and then juddered to a stop. "Okay," she said, wondering if it was safe to let go, "what was that?"

"That," the Doctor said, picking himself up, "was some kind of fantastically weird shielding device that had a very good go at stopping us materialising, and incidentally I sort of have no idea where we are."

"No idea as in end-of-the-world, middle-of-nowhere kind of place, or more like London with zeppelins?"

"Looks like…" The Doctor tapped a screen on the console. "Scotland actually, little town in Scotland called Hogsmeade…early October, 1995." He frowned. "Hogsmeade, Hogsmeade…huh."

"Been there before?" Rose asked.

"Never heard of it." He leaned away from the console, grinning. "Shall we have a look?" He bounded to the door and pulled it open, Rose behind him.

She stepped out, staring. The TARDIS had landed them in what looked for all the world like an ancient abandoned house: dim moonlight filtered through grimy, broken windows and shredded curtains, and dust covered every surface—except where something had disturbed it pretty violently. Rose walked into the next room carefully, wincing when the floorboards groaned under her weight, and went to the window on the far wall. The panes were too dirty to make out much of the world outside. Something that might once have been a chair lay in pieces against the wall, and the door to the hallway hung half off its hinges. Ashes from an old fireplace were scattered across the floor.

Rose shivered. "Almost looks…haunted, or something."

"Ghosts didn't do that." The Doctor hefted the chair leg, inspecting the end of it. "And I bet kids didn't either. Look at that—bite marks in the wood, something quite sharp and pretty large, and this—" He crouched, tracing a great scrape along the floorboards near the door. "Nice set of claws on this thing, too, whatever it is."

Something creaked. Rose turned in time to see a large, silver-grey wolf squeeze through the shattered doorway and into the room, its eyes fixed on the Doctor. Blood glistened at its mouth and in the fur along one leg.

"Doctor," Rose said very quietly, backing toward the wall and feeling for any kind of weapon. "Turn around."

He did, still talking to himself. "…and it's got a long reach, too, powerful muscles, something just…like…that." His eyes widened. "_Ah_."

Rose kept moving backward, willing the wolf not to attack. "It's between us and the TARDIS."

The Doctor stood slowly. "That it is. And I think—"

The wolf lunged.

"Guess what? Time to run!" The Doctor grabbed Rose's hand and pelted into the hallway.

They sprinted downstairs, the wolf pounding behind them. "Thought wolves didn't usually attack people," Rose panted.

"Oh, that's not a wolf." The Doctor pulled her into the nearest room, slammed the door, and locked it with his sonic screwdriver. "All kinds of little differences—pupils, snout shape, nice little tuft on the tail—"

The door shook as the wolf threw its body against it. Rose took a step back. "That's a werewolf?"

"Oh, yes." He looked around. "And this is a bit of a dead end, isn't it? Yeah, nice textbook example of a werewolf, really."

The wolf's claws scrabbled into the space under the door, raking wood chips from the floor. "Doesn't look like the other one." Rose turned, taking in the room: faded wallpaper covered in claw marks, battered floorboards marked with dark stains here and there, a pile of…something…in the corner that she had no desire to inspect, and not a stick of furniture or a single window.

"Oh, lycanthropes don't have to be anthropomorphic. Most aren't, I think…lots of different kinds. This one's probably got nothing to do with our werewolves. They all hunt humans, though." The door creaked as the werewolf smashed against it again. "And I chose pretty much the worst room possible, didn't I?"

"Looks like it, yeah," Rose said. "Don't suppose you've got a dog bone in one of those pockets or anything."

"Nah, those smell nasty." The Doctor crossed the room and aimed his sonic screwdriver at a spot on the wall. "This wood's already weak, though, and if I can hit the right frequency—"

The wallpaper split down the middle, the wood began to crack—and the door splintered in half as the werewolf heaved itself against it one last time. The Doctor whirled and pointed his sonic screwdriver at the werewolf. It cowered back, ears flattening at the high-pitched whine.

Rose kicked a hole in the wall to finish the sonic screwdriver's job. Not big enough. She kicked it again, scrambled through, and found herself in a ravaged kitchen. "Doctor, come on!"

He followed with some difficulty, looking put out when his sleeve tore on a jagged piece of wood. The werewolf shoved its head through the gap, snapping and growling at them both, but its shoulders couldn't fit. Snarling, it pulled back.

"The door, hurry!" the Doctor shouted. Together they dragged the remains of a table up the hallway and barricaded the room's door with it, trapping the werewolf inside—for the time being, anyway.

Rose returned to the kitchen and snatched up a broken chair leg, though considering what the werewolf had done to the chair upstairs, she couldn't imagine how it would help her much. "Okay, now what?"

"Good question. Excellent question." The Doctor unlocked the nearest window and tried to open it. "Stuck. Nice if our werewolf friend would just keep the windows oiled for us." The sonic screwdriver glowed blue, and he yanked on the window again. "That's not working either. Why isn't it working?"

Rose joined him at the window, looking behind her uneasily: by the sound of it, the werewolf was trying to claw and chew through the hole they'd made in the wall. "How much time have we got until—what, moonset?"

"Not too long, but—" The werewolf thrust its head through the hole, and this time it managed to fit one leg through as well. "Longer than we can wait in here, anyway."

And then another door creaked close by, and a voice called, "Remus? I heard voices, are you—"

"Don't come in!" the Doctor shouted.

Too late: a girl maybe five years older than Rose, with spiky pink hair and patched jeans, rounded the corner; and then there was another crash, more splintering of wood, and the werewolf forced its way into the kitchen.

"Oh,_blimey_," the girl said. She whipped a long, thin piece of wood from the waistband of her jeans, pointed it at the werewolf, and shouted, "_Stupefy_!" A jet of red light shot from the tip of the stick, catching the werewolf mid-leap and throwing it to the floor.

"That'll only hold him for a second," the girl said, hurrying them into what might once have been a sitting room. She slammed the door and pointed her wand at it. "_Impervius_!" The door trembled as the werewolf rammed into it. The girl turned to Rose and the Doctor, breathing hard. "He's been on the Wolfsbane so he _shouldn't _be too dangerous, but you probably startled him and what in Merlin's name are you _doing_ in here?"

"I'm wondering that myself," the Doctor said, scratching his head. "Don't think I'm not grateful, because I understand werewolf bites are just a little bit unpleasant, but—what exactly _was_that?"

The girl looked at them sideways. "Just…a charm, to—" She stopped, looking dismayed. "Oh, Merlin, are you Muggles?"

"Doctor," Rose said, "are you _sure_ we're in Scotland?"

"Scotland, yeah," he said without looking at her. "Sorry, um…what exactly are Muggles?"

"Nonmagical people," the girl said. "You _are_, aren't you? And this was supposed to be a day off…I hate removing memories."

The Doctor's eyebrows rose. "Can't blame you. Why would you need to do that?"

The girl blew out a long breath. "Well, since chances are you're not going to remember this anyway—" She frowned. "How _did_you get in here? I checked the wards yesterday and you shouldn't even have got into town if you really are Muggles."

Rose pushed her hair back from her face, feeling a headache coming on now that the adrenaline was wearing off. "We don't really know. Just sort of…showed up here."

"Yep, no idea," the Doctor said brightly. "My ship's upstairs if you want to see, though, unless your werewolf friend takes objection to that idea. Speaking of which, just why are you in here? I'm the Doctor, by the way, and this is Rose."

"Tonks," the girl said blankly, blinking at him as if trying to process what he'd just said. "Well, Nymphadora Tonks, actually, but anybody who calls me that gets hexed. Did you say your ship?"

"Ship, yeah, spaceship—well, sort of, she's actually not so good with the flying part. Nothing like her in the universe for eating up the Time Vortex, though."

"We were going after some werewolves in the future and ended up here," Rose put in. "Didn't know there was anything here till we saw the werewolf."

"You called him Remus, didn't you?" the Doctor asked.

Tonks bit her lip. The door rattled violently, but the charm held. "Well, I'm a witch," she said finally. "He's a wizard—well, when the moon's not full, obviously—and this…Hogsmeade is a wizarding community. This house is supposed to be haunted, but it's really just a place Remus sometimes uses to transform. That's what the wards are for."

"Told you it looked haunted," Rose muttered.

"Hang on, so there are wizards just here, or what?" the Doctor asked.

Tonks hesitated. "No, all over the world, but there are all kinds of laws to keep Muggles from discovering us. That's why you'll have to get your memories modified, and I'm kind of rubbish at that, which means taking you to the Ministry and all that _paperwork_…" She pinched the bridge of her nose. "Don't like having it done anyway. Doesn't seem right."

"Seriously, wizarding communities all over the world?"

"You didn't know?" Rose asked him.

He shook his head, staring at Tonks in fascination. "Well, a little maybe—rumors—but you've all been around for, what, thousands of years and I've never run into any of you until now? That's very—honestly, I'm impressed. You lot must be absurdly good at hiding."

"Yeah, that's what the Ministry and the Statute of Secrecy and that are for," Tonks said.

"The memory thing, right," the Doctor said. "So…why were you coming in here after a werewolf, again?"

The werewolf dragged its claws down the door and howled, making Rose jump. Tonks gazed out the window. "Almost time…he wouldn't want me here, but he was sick going into this transformation…threw up half his Wolfsbane Potion, and don't tell him I said that because he'll be embarrassed enough that he needs fussing over."

Rose grinned a little. "Kind of a bloke thing, isn't it? Never want to admit they could use some help."

"Okay…" The Doctor looked back and forth between them. "Suddenly I'm feeling outnumbered. When did that happen?"

Another howl from behind the door prevented Tonks from answering, and this time the howl turned ragged, fracturing into a half-human scream of pain as bones audibly broke, shifted, reformed. Tonks waited, her body tense and one hand on her wand, Rose and the Doctor forgotten, for the transformation to stop.

A moment passed, then another, and the cry faded into panting that sounded as if every breath hurt. Human. Tonks flicked her wand at the door, flung it open, and hurried inside, out of sight.

"Merlin, you look awful," Rose heard Tonks say. "_Accio Robe_—where'd you put your wand?"

"Pocket—Dora, I heard voices—are they—"

"They're fine, you didn't hurt anyone, now hold _still_ and let me look at that wound, Remus Lupin. You're the one I'm worried about just now."

"You shouldn't be here either," Remus murmured. "I could've…it isn't safe…"

"D'you think I'd be an Auror if I wanted to be safe? You need looking after, you know. Seeing as nobody else—Merlin, Remus, how'd you get that one?"

A pause. "I'm…not sure…suppose it must have been earlier…"

"_Bloody_ Ministry," Tonks said viciously. "If they put half the effort into even improving the Wolfsbane that they are in sticking their heads in the sand—but no, let's make it _impossible_ to get a job so most of them can't even get Wolfsbane, that makes loads of sense…"

Remus hissed. "Ow."

"Sorry, getting carried away—here, put that on it—wish I knew more first aid…"

"You never said—those people I heard—I know they were in here, but—"

"Yeah, it's weird…" Tonks lowered her voice so Rose had to strain to listen. "Thought maybe it was a couple dumb kids, but they're too old, so I wondered maybe a couple in here for a snog…"

The Doctor nudged Rose, one eyebrow raised in amusement. She elbowed him.

"No," Remus said, "no, there's…I know I smelled something that wasn't human, but I don't—" He swore. "Can't even _think_…"

"Well," Tonks said glumly, "probably doesn't matter, as they both seem to be Muggles. Still can't figure out how they got past the wards, though…"

"Can they _do_ that?" Rose whispered. "Erasing memories?"

"Well," the Doctor said, "they can _try_…"

"Sure they're Muggles?" Remus asked. "I should talk to them—"

"Hello," the Doctor said, sticking his head around the corner. "Talking about us?"

Rose stepped into the kitchen after him and got her first look at the werewolf in his human form. It must have been quite a feat to look exhausted, mortified, and protective all at once, but the werewolf managed it. He was older than Tonks, Rose thought, but not old enough for the amount of grey in his light brown hair, and his face was scarred and nearly as ashen. Tonks had knelt next to him, her bright hair a sharp contrast to his drab robes, which had definitely seen a lot of better days. So had Remus: blood spattered the floor around him and seeped through a bandage Tonks was pressing against his leg.

"Oh my God," Rose said, "what—are you all right?"

"I'm fine," Remus said tightly, not looking at any of them.

Tonks waved her wand, and another bandage unrolled from the tip. "No you're not, you prat, you're hurt and sick. Werewolf wounds don't heal like normal ones do," she explained, glancing up at Rose and the Doctor. "I barely passed my class on healing, but even I can do basic stuff, and they—don't respond to much."

"That so?" The Doctor crouched at Remus' other side. "Well, Remus Lupin, I'm called the Doctor, and I know you don't trust me—can't blame you really—but I'm fairly certain I can help you a bit, if you'll let me."

Remus met the Doctor's gaze, and Rose found herself holding her breath as she watched: ancient eyes in young faces, both of them, grief and loss and loneliness and pain—

She wondered if Remus had ever killed anyone.

Then Remus lowered his eyes and the moment was lost. "Yes," he said, "I…thank you."

"Don't thank me yet, we have to get upstairs first. The TARDIS has a medical bay—best around for the next couple thousand years at least—but she decided to park up there and I'm not too eager to try fighting those wards again to set her down here."

Remus got to his feet with some help from Tonks and the Doctor. He stood unsteadily for a moment, then took a step and gasped, pressing one hand to his side where fresh blood soaked through his robes. "Think I fell on something when I changed back," he said through gritted teeth.

They made their way upstairs, Remus repeatedly apologizing for needing the help until Tonks said she'd hex him silent if he didn't stop. Neither Tonks nor Remus seemed particularly astonished by the TARDIS's larger interior when they stepped inside.

The Doctor helped Remus to the medical bay to treat his wounds, leaving Tonks and Rose in the console room.

"Think I could use some caffeine after that," Rose said. "Want some tea?"

"Sure, but don't let me near your teakettle, I found out years ago it really is possible to burn tea."

"Seriously?" Rose pushed away from the console and headed down the corridor. "Stay behind me so you don't get lost, you wouldn't believe how confusing this place is."

"Just how big is it?"

"Don't let the Doctor hear you calling her 'it,' you don't want the lecture. She's…I don't even know quite how big. I think I spent half my first month on here getting lost every time I needed to use the loo. Here we go—kitchen."

"Bit retro, isn't it?" Tonks commented.

"Yeah, she redecorated after we visited the '50s. Does that sometimes." Rose pushed aside two alien devices of questionable origin and purpose and found a relatively normal teakettle.

"Hang on, you time travel?"

"'Swhat the Doctor does. Travels through time and space, helping people and saving the universe." Rose started the water heating up and leaned against the counter. "And I go with him. I've seen…all kinds of things—aliens and supernovas and the end of the world…and I'm just a London shopgirl. Still can't believe it sometimes."

Tonks grinned. "You're not a little bit in love with this Doctor bloke, are you?"

"S'pose I might be, yeah," Rose said. "What about you? Are you a little bit in love with that werewolf bloke?"

"Yeah, guess I am. He's…oh, he's just _good_, you know? And," she added reflectively, "he's really cute when he's embarrassed about something. Or when he's waxing ecstatic over Muggle poetry, which is often."

"And he's lonely."

Tonks nodded, her expression going solemn. "There was…he was in a war. Before my time. Our side lost a lot of people. But I think he's always been old. He was bitten as a child."

"Yeah," Rose said quietly. "The war never really ends, does it? Not for them."

Tonks hoisted herself up to sit on the table and arched an eyebrow at Rose, half-smiling. "So we're both attracted to lonely older men? That just doesn't sound good."

Rose laughed. "Reckon you haven't got a 900-year age difference to deal with, though…"

Tonks stared. "Okay, he's…not human."

"Time Lord. Last in the universe, actually."

"Did I hear my name?" The Doctor entered the kitchen, followed by a limping but much-improved Remus.

Tonks hopped off the table and gave Remus a kiss on the forehead. "That was fast."

"He wasn't joking about having the best medical facility for thousands of years. Somehow I don't think 'Muggle' quite covers it, in this case."

"Muggle," the Doctor repeated. "Sounds so…inelegant. Just because I haven't got a wand…"

"I'd call fitting all this into a blue box magic," Tonks said. "We do that, sort of."

"Time Lord science. Bigger on the inside." The Doctor helped himself to some tea, a particularly strong kind Rose had tried once and sworn never to touch again. "Of course, most forms of magic I've run into just seem to be science poorly understood."

"We do understand our magic." Remus leaned against a chair, the scars on his hands white where he gripped its back. "I could bore you stupid with details about werewolf anatomy and physiology, how the disease is transmitted, everything—but we still can't cure it, of course," he added, bitterness sharpening his voice. "Cheaper to restrict us."

"That's not fair," Rose muttered.

"Wait, hold on," the Doctor said, mug frozen halfway to his mouth. "You've studied up on werewolves, then? Not just old legends—most of which isn't true, by the way—but real studies?"

Remus nodded. "Some of both, actually."

The Doctor smiled. "How would the two of you like to see the future and help Rose and me save the world?"

* * *

"This is London?" Tonks asked weakly. 

"Middle of Old London, AD 2203. The police haven't been in this part of it for—oh, a dozen years by now, I think," the Doctor said. "Good place to disappear—or hide while you're trying to take over the world, if you're into that sort of thing."

Derelict buildings loomed above them on all sides, windows shattered and dark like staring, empty eyes. Cracks and blast holes scarred the ancient cobblestone street ahead, and Rose could smell a faint metallic tang in the air mixed with the heavy scent of exhaust fumes.

"I think we are in rats' alley, where the dead men lost their bones," Remus murmured.

The Doctor clapped him on the shoulder. "Let us go then, through certain half-deserted streets—or at least we can hope they're deserted."

Rose very much doubted that would be the case, and she felt oddly comforted when Remus and Tonks drew their wands (even if Tonks did trip on the first crack in the paving stones). They passed a group of hollow-eyed teenagers, all hooked intravenously to a single container of some faintly glowing liquid; then a woman wearing more tattoos than clothes and carrying a gun at her side, who watched with a dark, calculating gaze as they walked by. No one spoke to them, but Rose found herself wishing she and the Doctor didn't stand out so much—Remus' clothes were dark enough, and Tonks had put on a black jacket at some point over her bright t-shirt (Rose got a shock when she realized Tonks's hair had switched to black as well), but Rose and the Doctor didn't _really_ fit in.

The abandoned warehouse the Doctor led them to didn't exactly look more welcoming, though. The building stretched nearly the length of the entire street, and its windowless walls—one of which had apparently been sprayed with acid at one point, and all of which bore bullet holes—reached several storeys high.

"Sure this is it?" Rose asked.

The Doctor glanced at Remus, who raised his wand and stepped closer. "_Lumos_." Light glowed from the tip of his wand, and he flattened one hand against the wall. "Look at this." Scratched onto the wall was a tiny, stylized skull—human…except for its pointed teeth and an elongated snout that gave the little drawing the look of an optical illusion. Dark scarlet blots marked the skull's eyes.

Rose decided she didn't want to know what the red marks were. "That's a…werewolf symbol?"

"Not exactly, but the drawings I've seen of werewolf anatomy during a transformation are similar." Remus dropped his hand back to his side. "And…I can feel them." He looked up at the darkening sky, swallowing hard. "It's too close to the moon…"

"I won't ask you to go through another transformation this soon," the Doctor said, "but there is a full moon tonight. Do you want to go back to the TARDIS?"

Remus shook his head.

"Gryffindor," Tonks whispered, rolling her eyes.

"I've been on the Wolfsbane," Remus insisted. "I'll change eventually no matter what, but as long as the light of the full moon doesn't touch me, I can hold it off for—well, a while, anyway. It'll be slower anyway, with all these clouds—"

"That's pollution, not clouds," the Doctor said. "Even better. Well, for your purposes, anyway."

"Oh," Remus said blankly. "Well. Yes. I suppose."

Between the Doctor's sonic screwdriver and a charm from Tonks, they got the door unlocked and rolled it open. Rose stepped inside and stumbled, nauseated, as the suddenly overwhelming and heavy metallic scent struck her like a physical blow. She clapped a hand to her mouth. "What _is_ that?"

"Blood," the Doctor said.

Remus and Tonks lit their wands, revealing a cavernous open space of steel and concrete. Pipes and wires snaked up the wall behind them, but the other walls stretched away into darkness. Almost out of the range of wandlight stood the outline of a tall metal shelf.

"Werewolves in a warehouse," the Doctor said, sliding the door shut behind them. "Come on, then…"

They passed rows and rows of high shelves, scattered with shadowy boxes and bundles. Something skittered down one aisle into the dark when Tonks tripped over a cable spread across the floor (Remus grabbed her arm to steady her and didn't let go of her hand even after she'd regained her balance).

"This isn't, I dunno, enchanted to make it seem bigger, is it?" Rose asked, her voice hushed. Their footsteps didn't cast any echoes, she'd realized; the place was too _quiet_, too…dead. "Feels like we aren't getting anywhere."

"It's not," Remus murmured. "There's magic here, but it's…different."

The Doctor glanced at him, eyebrows raised. "These are aliens, you know. Far as I know—and I'll admit I was a tad distracted when I met one last time—they can't do magic."

Tonks halted and raised her wand. "Maybe they can."

Rose stepped around her to see. They'd come to a crossroad of sorts, a wider aisle splitting off on both sides of the main walkway. A pool of dim light fell in the centre from some sort of skylight in the much lower ceiling, illuminating a large circular pattern drawn on the floor directly beneath the skylight.

Remus stopped well back from the circle of moonlight, his posture tense.

"You all right?" Rose asked.

He didn't look at her. "The moon is full. I can feel it…pulls at the bones…" He spread his fingers out and stared at his hands as if expecting them to sprout claws any second. "I can hold the change off, just not indefinitely, even if I stay inside."

"How does that work, by the way?" The Doctor stood across the circle from them, just outside the moonlight, hands in the pockets of his trenchcoat. "How moonlight triggers the change? I've always wondered—well, always, I mean since—oh, however long ago it was, several months maybe? I've run into a few other werewolves before, but I'm not sure how they did it either. The right wavelength, probably, maybe a little bit of the effect of the moon's gravity…" He gave Remus a speculative look. "What would happen if you went to the moon? Or went somewhere there wasn't a moon at all?"

Remus shook his head. "I truly don't know. That's one thing we haven't figured out. It just happens—the full moon rises, and…we go mad."

"And spend the time in between trying to convince everyone you're still human." The Doctor stepped into the circle and stared up at the skylight. "Okay, this looks weirdly familiar…"

"What is it?" Rose asked, moving closer.

"No idea. Haven't seen it yet." He rubbed his chin. "That's no ordinary skylight, though—see how it comes down to a point there in the middle? It's even faceted a bit—so if that's some kind of focusing crystal…what's it focusing on, I wonder?" He crouched, tracing his fingers along the dark red patterns on the floor, and then bent over and licked it.

Tonks wolf-whistled. Rose quickly hid her grin as the Doctor straightened, giving Tonks a dirty look. "If you've finished objectifying me, you might want to have a look at this."

They did, Remus still a good three paces back, and Rose bent to study the inscription on the floor. Twisted shapes and arcane lettering spiralled in concentric rings down to an open circle at the centre, just big enough for the Doctor to stand in, although he could have lain down with room to spare across the entire drawing. Faint lines split through the rings, coming to points on the outside circle; it took Rose a moment to realize the lines formed a five-pointed star.

"That's blood," the Doctor said. "Human blood. From more than one person, too—it's all been mixed together. Would take a lot for all this, though."

Tonks fingered her wand. "Whoever did this was familiar with the Dark Arts…I've seen things like this before. On the job, I mean. Not quite sure what it does, though."

"Doctor," Rose said slowly, "shouldn't we be able to read this?"

He nodded. "Could be a few different reasons we can't, and I don't like any of them an awful lot. Seems I was wrong about the magic part, though."

"So you don't know what it is?" Tonks asked.

"Oh, I've got some ideas…"

"I can read it," Remus said suddenly. "I took Ancient Runes at Hogwarts, it looks close to that…" He squinted, walking a slow circle around the inscription.

"The Dark Arts tends to have this sort of thing," Tonks explained to Rose and the Doctor. "Complicated spells with blood and bone—if it's more like a potion, where the ingredients and their combinations have the right kind of magical properties, you might not need magic yourself to do it. And yes, I _did_ do well in Potions, whatever Snape tells you."

The Doctor looked back at the inscription. "It repeats…four times, one at each angle formed by the aisles here—so the moonlight strikes here, at the very centre of the building and inscription with this little crossroad as a focal point."

Remus nodded. "Right, I've got it," he said finally. "_Moonlight shows the true form. Life of your prey calls you. Fix mind, heart, and bone. Boil_…sorry, _purge_…_the stain. Bind blood and bone. Moonlight shows the true form._" He looked up. "Not the most elegant translation, I'm afraid. But I think it's some kind of binding spell."

"Activated by moonlight focused through this crystal here, is that it? But to do what, exactly?" The Doctor began to pace. "Moonlight shows the true form—so, what, it keeps them transformed? That's not helpful—_unless_—" He ran both hands through his hair, making it stick out in all directions. "Alien cell, slowly developing and coming to consciousness, remembering—so what does it want? It wants to make sure it survives, and then it probably wants the same thing as last time—"

"The Empire of the Wolf," Rose murmured. "Spaceships run by steam."

"Yes, steampunk, very Victorian. Only, I don't know, I suppose it can make use of whatever technology it gets, assuming it gets to the right person…and it had human servants last time, crazy cult monk guys, not real pleasant, and they orchestrated a massively complicated plot—only it didn't work, did it? Which was mostly my fault. But now it's going to try something different…" He turned, staring back up at the crystal, moonlight casting alien shadows on his face. "A binding spell…full moon, focuses a narrow bean here—_but_—no, it's only lined up perfectly on this spot once a year, for…oh, four minutes? Four minutes a year to use this spot? Doesn't seem worth it, really…"

"It's been used, though," Tonks said. "Spells like this leave a magical signature. It's been used several times, I think."

Rose looked around uneasily, wishing she could see further into the dark. "Real question is, why isn't anyone here? This is the right night, isn't it?"

"Absatively," the Doctor said. "Ooh, don't ever let me say that again. No, it's right, few more minutes maybe—" He stopped, his gaze falling on one of the shelves, and then he whirled on Remus. "You're the expert, how is lycanthropy transmitted? By biting, of course, but what is it, some sort of pathogen? Something like venom?"

"I'm not an alien, so whatever you're thinking, it might not be—"

"No, completely human, I know, but you're both light-modulated species triggered by the same specific wavelength, and I really don't think we've got much time here."

"It's in all a werewolf's bodily fluids," Remus said, going a little pink. "The infection. So the bite has to break skin, usually, but there've been cases—a person already had an open wound and was licked by a werewolf there, or even sometimes if they fight back and get the werewolf's blood on an existing cut—"

"So," the Doctor said, "isolate the infection—in werewolf blood, say—"

"It's nearly impossible," Remus objected. "Our blood's human when we're not transformed, and if you kill one in wolf form, it reverts back to a human just before the point of death. And getting close to one that's transformed, that's just dangerous."

"That other wolf—back with Queen Victoria—he tore apart the cage like it was nothing," Rose said.

"Right," the Doctor pressed, "but say you could get close enough, say you could get some pure werewolf blood, could you infect someone with it? Someone important? Lot more convenient than arranging to get a VIP out here."

"I suppose," Remus said reluctantly. "But even if you _could_—and it sounds like it'd be even harder with this kind—werewolf blood is very…unstable. Add just about anything to it and your potion will probably—explode, or melt, or something. Even exposing it to air can sometimes cause reactions that would make it useless for this."

"Oh, come on, let's see a little creativity! They've had hundreds of years dedicated to a single goal, and I think they've figured out_something_."

Rose frowned at him. "When did you start saying _they_? I thought the—the alien bit only passed along to one person."

He raised an eyebrow and pointed behind her. She turned: the nearest shelf held a row of glass vials, all full of…something dark. "Oh my God, is that blood?"

The Doctor stepped closer and passed his sonic screwdriver down the row. "Yep. One hundred percent pure werewolf blood. Pieces of a fragmented alien consciousness, waiting to be put back together again and sent into some new host."

Remus looked back at the circle on the floor. "Bind blood and bone…"

"Moon triggers binding spell, werewolf transforms and is held in place, untransformed werewolf takes some blood and uses the binding spell to seal it so it'll keep better, and time's up for another year. They've been patient."

"You keep saying _they_," Rose said. "Why—"

"It had to survive, remember? It learned to adapt to human hosts in the first place, and now it learned to split itself."

"Queen Victoria and her kids, yeah?" Rose asked, remembering. "So…each bit starts its own line somehow, and then—what, when the alien part wakes up, they've got…some sort of hive mind? And then they have to find each other—"

"And recombine all of their blood to pass properly into some new host. Pick the right one and the world is yours. The Empire of the Wolf."

"So…any brilliant ideas on how to stop them?"

"Yeah, working on that."

"Why can't we just destroy the blood?" Tonks raised her wand. "_Reducto_!" The spell hit an invisible barrier at the shelf's edge and bounced back at Tonks so quickly she barely had time to duck. She straightened, rubbing her shoulder. "Just a graze," she said to Remus' worried look. "Okay, that's why. Some backblast…I'd bet a couple Galleons somebody in this line met up with some real Dark wizards even if the—hosts, I guess—weren't magic. You can't get this stuff from books."

Remus hissed. "They're coming."

Rose stepped back, heart pounding. Tall forms loped toward them, eyes glinted through the dark at the other end of the long aisle: still human.

"They've been waiting," Remus whispered. "Somewhere away from the moon, maybe underground…" He squeezed his eyes shut, rubbing at his temples. "When the moon's directly overhead here, I don't think I'll be able to hold back the change."

Tonks swore. "And werewolves are resistant to most spells. Great."

"Come on then, no time for anything else—" The Doctor pointed his sonic screwdriver up at the crystal in the skylight. "If I can hit it right—try your wand, would you?"

Blue light from the screwdriver and white light from Tonks's wand blasted into the crystal. Remus grabbed Rose's hand, pulling her back as the untransformed werewolves broke into a run. They hid behind the nearest shelf, joined a moment later by Tonks and the Doctor.

"Didn't break," the Doctor whispered. "Might've weakened it, but—"

The werewolves clustered around the inscription, focused and silent—didn't speak, didn't stop moving to think, didn't make a sound. Why talk when a single alien consciousness bound them together, had hollowed out all their souls to control them from the inside?

Wasn't like there'd be much hope against them once they all transformed, either. Four minutes, the Doctor said?

No reason to deal with intruders yet either, since the werewolves would probably want a post-transformation snack.

(Gallows humour. Good sign she'd been around the Doctor too long.)

Three werewolves gathered up the vials and brought them to another werewolf holding a large metal goblet—silver? How much sense would that make? One by one, the first werewolf uncorked the vials and poured them into the goblet, letting the vials drop to shatter on the floor. The smell of blood in the air grew stronger.

The werewolf with the goblet set it in the centre of the circle, stood back, and waited.

Remus' knuckles showed white around his wand as the moonlight grew stronger. "It's still unstable," he muttered, his voice all but inaudible. "_Really_ unstable. Blood and silver…"

"What if you diluted it?" Rose whispered. "What if it wasn't…pure…when the moonlight hit it?"

He looked at her, just barely; she could see the pull of the moonlight on his eyes. "I don't know." He paused. "You want a distraction."

"Might be nice, yeah."

"Rose Tyler, are you scheming something?" the Doctor asked.

"Think I am," she said.

Remus scrambled to his feet and stepped into full view of the werewolves, his movements short and pained. "You're not the only lycanthrope here," he said; even his already-hoarse voice was beginning to roughen. A little longer and he'd be just as dangerous as the alien werewolves, who'd turned as one to stare at him. "Put out a call and every werewolf in the world would join you. We've been beat down too long—"

Rose stopped listening and crawled through the open shelf before she lost her nerve. She circled around behind the werewolves, keeping in the dark, knowing they'd hear her or smell her at any second, fumbling a small knife out of her pocket. She halted across from Remus—and was startled to realize the Doctor had followed her.

"Weren't paying attention, were you?" he whispered, grinning. His gaze fell on the pocket-knife. "Time Lord blood does funny things when you mix it with anything else."

"Good," Rose said, snapping open the knife and jabbing it into her thumb. A bead of bright red blood oozed out. The Doctor took the knife, just as Remus dropped to the floor and Tonks flung something into the air—and fireworks exploded.

"Don't tell Jackie about this, all right?" the Doctor shouted in Rose's ear, his palm glimmering wetly in the flashing light.

Rose flung herself forward. A werewolf grabbed for her, she caught a glimpse of teeth growing, sharpening, dodged and reached the goblet at the same time as the Doctor, dropped to her knees and squeezed a drop of blood into it.

A shaft of moonlight stabbed down through the crystal, nearly blinding her with its intensity, and then a clawed hand grabbed her hair, yanking her back—a flare of blue light, the claws let go, and she was running hand in hand with the Doctor as moonlight fractured through cracks in the skylight and werewolf after werewolf began to twist and spasm in the throes of transformation.

They reached Remus and Tonks just as an explosion ripped through the air behind them, throwing Rose and the Doctor to the ground.

"Hold on!" Tonks shouted. Rose gripped the Doctor's hand, felt Tonks grab her arm, and everything went black and there was pressure everywhere, she couldn't breathe—

And she collapsed on the floor of the TARDIS.

The Doctor leaped to his feet and yanked the door open. An explosion a street or two away lit the night sky outside. He closed the door, bounded to the console, and coaxed the TARDIS into life.

"…and that's why Potions class sends more people to the hospital wing than any other." Tonks sat up and peered down at Rose, who hadn't moved, still enjoying the comforting thrum of the TARDIS around her. "You all right there? Even Side-Along Apparition's a little rough the first time or so. Still got all your body parts?"

"Hope so." Rose flexed her fingers; the cut was beginning to throb.

Remus pushed himself upright with a groan. "The moon's gone…and I'm…" He looked down at his hands again.

"Completely human." The Doctor stretched across the console and hit a prominent button. "I can't cure you, but if you stay in the TARDIS or at least away from any moons like your own, I imagine you'd stay that way." He flicked another switch, and the TARDIS settled back on solid ground. Rose climbed to her feet and saw on the console screen the same old house they'd landed in before.

Remus went very still. "Go with you, you mean?"

"You and Tonks both, if you like—see the stars, save the universe once or twice, make more things blow up, take Tonks out to eat at Milliways if you're _very_ lucky—might even meet some friendlier werewolves. Hard to say."

Tonks and Remus exchanged a long look, and then Remus sighed. "I won't speak for Dora, but—I can't go. Not with Voldemort back. It's…there's a war coming. And I remember last time too well. I suppose now you've met us and you know about our world, you have a good idea how it'll all end…but I need to be there for all of it."

"Oh, trust you to be responsible," Tonks said. She dropped a kiss on the bridge of his nose and helped him up. "You're right, of course, much as I hate to admit it."

"Bet we'll see you again, though," Rose said. "Things sort of…happen that way sometimes." Impulsively, she gave both of them a hug.

The Doctor leaned against the console. "Might," he agreed. "The TARDIS is a little fussy these days, but I think she likes you."

Tonks grinned. "I'll keep an eye out for you then, girl," she said, patting one of the coral-like supports. "Sirius will be terribly jealous when we tell him about this. Oh—" She wrinkled her nose, and her hair turned back to bright pink. "That's better." With a last smile for Rose, she left the TARDIS.

Remus hesitated a moment longer. "Thank you," he said finally, and followed Tonks out, shutting the door behind him.


End file.
